Human Nutrition

Question 1

Autotrophs Vs Heterotrophs

Answer 1

• Autotrophs can make their own food while heterotrophs cannot
e.g. plants, some protists and some bacteria.

•Heterotrophs are unable to make their own food and rely on outside sources for energy
e.g. animals, fungi, some bacteria.

Question 2

Why do we need food?

Answer 2

• Provides energy (esp. carbs and fats).
• Growth and repair of damaged tissues (proteins).
• Regulation of body processes (vitamins, water and mineral salts).

Question 3

What is the purpose of the process ‘Digestion’?

Answer 3

Digestion allows heterotrophs to create simpler soluble nutrients that they can absorb from the larger complex, insoluble molecules they consume.

Question 4

What are the 5 main processes in Nutrition?

Answer 4

• Ingestion: the process of taking food or drink or another substance into the alimentary canal, typically by swallowing.
• Digestion: the mechanical and chemical processes in the body that change solid, insoluble food into simpler, soluble substances.
• Absorption: the absorbing of the end products of digestion into the bloodstream in the small intestine.

•Assimilation: when cells absorb nutrients from
the blood and use them to build new cell structures and compounds.

•Egestion: the process where undigested remains are removed from the body during defecation in the form of faeces.